<?php

/**
 * Author : smallchicken
 * Time   : 2009年6月8日16:46:05
 * mode 1 : 强制裁剪，生成图片严格按照需要，不足放大，超过裁剪，图片始终铺满
 * mode 2 : 和1类似，但不足的时候 不放大 会产生补白，可以用png消除。
 * mode 3 : 只缩放，不裁剪，保留全部图片信息，会产生补白，
 * mode 4 : 只缩放，不裁剪，保留全部图片信息，生成图片大小为最终缩放后的图片有效信息的实际大小，不产生补白
 * 默认补白为白色，如果要使补白成透明像素，请使用SaveAlpha()方法代替SaveImage()方法
 *
 * 调用方法：
 *
 * $ic=new ImageCrop('old.jpg','afterCrop.jpg');
 * $ic->Crop(120,80,2);
 * $ic->SaveImage();
 *        //$ic->SaveAlpha();将补白变成透明像素保存
 * $ic->destory();
 *
 *
 */

namespace app\libraries; 
 
class ImageCrop {

	var $sImage;
	var $dImage;
	var $src_file;
	var $dst_file;
	var $src_width;
	var $src_height;
	var $src_ext;
	var $src_type;

	function __construct($src_file, $dst_file = '') {
		$this -> src_file = $src_file;
		$this -> dst_file = $dst_file;
		$this -> LoadImage();
	}

	function SetSrcFile($src_file) {
		$this -> src_file = $src_file;
	}

	function SetDstFile($dst_file) {
		$this -> dst_file = $dst_file;
	}

	function LoadImage() {
		list($this -> src_width, $this -> src_height, $this -> src_type) = getimagesize($this -> src_file);
		switch($this->src_type) {
			case IMAGETYPE_JPEG :
				$this -> sImage = imagecreatefromjpeg($this -> src_file);
				$this -> ext = 'jpg';
				break;
			case IMAGETYPE_PNG :
				$this -> sImage = imagecreatefrompng($this -> src_file);
				$this -> ext = 'png';
				break;
			case IMAGETYPE_GIF :
				$this -> sImage = imagecreatefromgif($this -> src_file);
				$this -> ext = 'gif';
				break;
			default :
				exit();
		}
	}

	function SaveImage($fileName = '') {
		$this -> dst_file = $fileName ? $fileName : $this -> dst_file;
		switch($this->src_type) {
			case IMAGETYPE_JPEG :
				imagejpeg($this -> dImage, $this -> dst_file, 100);
				break;
			case IMAGETYPE_PNG :
				imagepng($this -> dImage, $this -> dst_file);
				break;
			case IMAGETYPE_GIF :
				imagegif($this -> dImage, $this -> dst_file);
				break;
			default :
				break;
		}
	}

	function OutImage() {
		switch($this->src_type) {
			case IMAGETYPE_JPEG :
				header('Content-type: image/jpeg');
				imagejpeg($this -> dImage);
				break;
			case IMAGETYPE_PNG :
				header('Content-type: image/png');
				imagepng($this -> dImage);
				break;
			case IMAGETYPE_GIF :
				header('Content-type: image/gif');
				imagegif($this -> dImage);
				break;
			default :
				break;
		}
	}

	function SaveAlpha($fileName = '') {
		$this -> dst_file = $fileName ? $fileName . '.png' : $this -> dst_file . '.png';
		imagesavealpha($this -> dImage, true);
		imagepng($this -> dImage, $this -> dst_file);
	}

	function OutAlpha() {
		imagesavealpha($this -> dImage, true);
		header('Content-type: image/png');
		imagepng($this -> dImage);
	}

	function destory() {
		imagedestroy($this -> sImage);
		imagedestroy($this -> dImage);
	}

	function Crop($dst_width, $dst_height, $mode = 1, $dst_file = '') {
		if ($dst_file)
			$this -> dst_file = $dst_file;
		$this -> dImage = imagecreatetruecolor($dst_width, $dst_height);

		$bg = imagecolorallocatealpha($this -> dImage, 255, 255, 255, 127);
		imagefill($this -> dImage, 0, 0, $bg);
		imagecolortransparent($this -> dImage, $bg);

		$ratio_w = 1.0 * $dst_width / $this -> src_width;
		$ratio_h = 1.0 * $dst_height / $this -> src_height;
		$ratio = 1;
		switch($mode) {
			case 1 :
				// always crop
				if (($ratio_w < 1 && $ratio_h < 1) || ($ratio_w > 1 && $ratio_h > 1)) {
					$ratio = $ratio_w < $ratio_h ? $ratio_h : $ratio_w;
					$tmp_w = (int)($dst_width / $ratio);
					$tmp_h = (int)($dst_height / $ratio);
					$tmp_img = imagecreatetruecolor($tmp_w, $tmp_h);
					$src_x = (int)(($this -> src_width - $tmp_w) / 2);
					$src_y = (int)(($this -> src_height - $tmp_h) / 2);
					imagecopy($tmp_img, $this -> sImage, 0, 0, $src_x, $src_y, $tmp_w, $tmp_h);
					imagecopyresampled($this -> dImage, $tmp_img, 0, 0, 0, 0, $dst_width, $dst_height, $tmp_w, $tmp_h);
					imagedestroy($tmp_img);
				} else {
					$ratio = $ratio_w < $ratio_h ? $ratio_h : $ratio_w;
					$tmp_w = (int)($this -> src_width * $ratio);
					$tmp_h = (int)($this -> src_height * $ratio);
					$tmp_img = imagecreatetruecolor($tmp_w, $tmp_h);
					imagecopyresampled($tmp_img, $this -> sImage, 0, 0, 0, 0, $tmp_w, $tmp_h, $this -> src_width, $this -> src_height);
					$src_x = (int)($tmp_w - $dst_width) / 2;
					$src_y = (int)($tmp_h - $dst_height) / 2;
					imagecopy($this -> dImage, $tmp_img, 0, 0, $src_x, $src_y, $dst_width, $dst_height);
					imagedestroy($tmp_img);
				}
				break;
			case 2 :
				// only small
				if ($ratio_w < 1 && $ratio_h < 1) {
					$ratio = $ratio_w < $ratio_h ? $ratio_h : $ratio_w;
					$tmp_w = (int)($dst_width / $ratio);
					$tmp_h = (int)($dst_height / $ratio);
					$tmp_img = imagecreatetruecolor($tmp_w, $tmp_h);
					$src_x = (int)($this -> src_width - $tmp_w) / 2;
					$src_y = (int)($this -> src_height - $tmp_h) / 2;
					imagecopy($tmp_img, $this -> sImage, 0, 0, $src_x, $src_y, $tmp_w, $tmp_h);
					imagecopyresampled($this -> dImage, $tmp_img, 0, 0, 0, 0, $dst_width, $dst_height, $tmp_w, $tmp_h);
					imagedestroy($tmp_img);
				} elseif ($ratio_w > 1 && $ratio_h > 1) {
					$dst_x = (int) abs($dst_width - $this -> src_width) / 2;
					$dst_y = (int) abs($dst_height - $this -> src_height) / 2;
					imagecopy($this -> dImage, $this -> sImage, $dst_x, $dst_y, 0, 0, $this -> src_width, $this -> src_height);
				} else {
					$src_x = 0;
					$dst_x = 0;
					$src_y = 0;
					$dst_y = 0;
					if (($dst_width - $this -> src_width) < 0) {
						$src_x = (int)($this -> src_width - $dst_width) / 2;
						$dst_x = 0;
					} else {
						$src_x = 0;
						$dst_x = (int)($dst_width - $this -> src_width) / 2;
					}

					if (($dst_height - $this -> src_height) < 0) {
						$src_y = (int)($this -> src_height - $dst_height) / 2;
						$dst_y = 0;
					} else {
						$src_y = 0;
						$dst_y = (int)($dst_height - $this -> src_height) / 2;
					}
					imagecopy($this -> dImage, $this -> sImage, $dst_x, $dst_y, $src_x, $src_y, $this -> src_width, $this -> src_height);
				}
				break;
			case 3 :
				// keep all image size and create need size
				if ($ratio_w > 1 && $ratio_h > 1) {
					$dst_x = (int)(abs($dst_width - $this -> src_width) / 2);
					$dst_y = (int)(abs($dst_height - $this -> src_height) / 2);
					imagecopy($this -> dImage, $this -> sImage, $dst_x, $dst_y, 0, 0, $this -> src_width, $this -> src_height);
				} else {
					$ratio = $ratio_w > $ratio_h ? $ratio_h : $ratio_w;
					$tmp_w = (int)($this -> src_width * $ratio);
					$tmp_h = (int)($this -> src_height * $ratio);
					$tmp_img = imagecreatetruecolor($tmp_w, $tmp_h);
					imagecopyresampled($tmp_img, $this -> sImage, 0, 0, 0, 0, $tmp_w, $tmp_h, $this -> src_width, $this -> src_height);
					$dst_x = (int)(abs($tmp_w - $dst_width) / 2);
					$dst_y = (int)(abs($tmp_h - $dst_height) / 2);
					imagecopy($this -> dImage, $tmp_img, $dst_x, $dst_y, 0, 0, $tmp_w, $tmp_h);
					imagedestroy($tmp_img);
				}
				break;
			case 4 :
				// keep all image but create actually size
				if ($ratio_w > 1 && $ratio_h > 1) {
					$this -> dImage = imagecreatetruecolor($this -> src_width, $this -> src_height);
					imagecopy($this -> dImage, $this -> sImage, 0, 0, 0, 0, $this -> src_width, $this -> src_height);
				} else {
					$ratio = $ratio_w > $ratio_h ? $ratio_h : $ratio_w;
					$tmp_w = (int)($this -> src_width * $ratio);
					$tmp_h = (int)($this -> src_height * $ratio);
					$this -> dImage = imagecreatetruecolor($tmp_w, $tmp_h);
					imagecopyresampled($this -> dImage, $this -> sImage, 0, 0, 0, 0, $tmp_w, $tmp_h, $this -> src_width, $this -> src_height);
				}
				break;
		}
	}// end Crop

}
?>